Worm farming

Worms can do wonders for the garden: they aerate the soil and their castings are an excellent fertilizer. To get a constant supply of this worm fertilizer as well as extra worms for the garden, start a worm farm.

Use Red Worms or Tiger Worms only (available from most plant nurseries). The common garden/earth worm is not suitable.

Setting up the system

Worm farms are simple structures. They consist of three or four stackable trays made of wood. The worms live in the trays and simply wriggle their way up from the lowest tray into the one above, where they can smell fresh food fruit, vegetable and other scraps that might otherwise go to waste. These scraps are turned into the castings that make such good fertilizer.

The drip tray has a solid floor to catch liquid run-off that percolates down from the upper trays.

The upper trays are perforated to let the worms move up through the floor to reach fresh food supplies. These 'holey' trays lock into each other and are deep enough to leave enough room for the worms to move about without being squashed.

To create congenial living conditions for the worms, you need newspaper and soil to start the farm and a continuing supply of suitable food scraps.

Starting the farm

On top of the base fit an upper (holey) tray #1 that has been lined with bedding - peat moss and a couple of handfuls of soil. You can use other kinds of bedding, such as shredded newspaper, manure, coconut fiber, etc.
 One of the best choices for bedding is a mix of dried dead leaves, shredded cardboard and small amount of sandy soil. The leaves should be aged for several months.   The amount of bedding material depends on a quantity of worms. 3/4 of a tray would be enough for 2lb.
Spray lightly with fresh (better non chlorinated) water, the bedding to water ratio is 1:3, so 1oz of dead leaves and shredded cardboard  should be soaked in 3oz of water. The bedding should be dump, but not wet. A good test is when you squeeze a handful of bedding the water doesn't drip.  

Add the Red or Tiger worms along with a small amount of food scraps buried in the bedding. Exclude light from the upper tray and keep it moist by covering it with cover. Allow the farm to settle in for a couple of weeks before lifting the cover and putting in more food scraps. Bury food scraps in different spots of the tray covering them with bedding material, add some more bedding if necessary. Check on the tray's progress and add more food scraps as the worms grow and multiply. Make sure that your worms have enough food, but don't overfeed them - uneaten food will simply rot, resulting in a smelly farm and unhappy worms.

When holey tray #1 is full of worms and worm castings, remove the cover and place holey tray #2 on top. Put new bedding and food scraps in tray #2 and, again, exclude light and keep the contents moist. In about a week the worms from tray #1 will have moved up into the fresh food in tray #2, leaving behind worm castings that can be spread on the garden.

Hints for happy worms

Light

Worms usually live underground so they thrive in an environment that is cool, dark and moist.

Moisture

Worms like moisture and should not be allowed to dry out. A light spray of fresh water when the worm farm is first constructed will generally provide sufficient moisture for the farm, but sometimes more spraying is required during the farm operation. If you add too much extra water or allow rainwater to get into the bins, the worms may drown.

Food

Worms are voracious eaters. Once the worms are settled in and growing, give them a good supply of suitable food.

Worms like most vegetable and fruit scraps (except onions and citrus), but as worms do not have teeth, scraps should be cut into small pieces: waste from a vegetable juicer is ideal. Worms need a small amount of sand (mixed with garden soil) added to the food for their digestion system.

Worms also like:

• soaked and ripped pizza boxes

• shredded and soaked cardboard

• paper

• fruit and vegetable (except onions and citrus)

• leaves

• dirt

• hair

• egg shells.

It's a good idea to store the food scraps in a plastic container for a week before giving them to worms. The worms like this "prefermented" food.

Worms will eat meat but it can lead to smells and maggots in the worm farm.

Plants from the onion family (including garlic and shallots) and citrus fruits contain volatile oils. If any of these are included in the food scraps the worms will climb out of their bin to get away from the smell.

If this happens to your worm farm, place another bin with a fresh food supply on top of the contaminated bin. Once the worms have climbed out of the contaminated bin (about a week) remove it and use the castings for normal compost - the uneaten onion and citrus won't hurt the garden.

Worm farm 'produce'

Castings can go straight onto the garden or pot plants. If they are covered with mulch their moisture and nutrient content will be conserved.

An excellent liquid fertilizer can be made from the castings by adding water until the mixture looks like weak tea. African violets and other plants that like being fed from the roots, just love this mixture.

Moisture drained from the worm farm's bottom crate is also a good liquid fertilizer, but it too should be diluted.

Excess worms can be put in the compost heap where they will help speed up the composting process.

June 2008